The Water Lens is a custom-machined lens that uses a flexible lens element to adjust focus. Contrary to traditional camera lenses that shift the position of hard optics, the water lens acts more like the human eye, actually changing the curvature of the lens to pull objects into focus. The lens is machined from aluminum and the flexible element consists of a telescoping cylinder filled with water and sealed at one end by latex. As the cylinder is rotated, its length is either increased or decreased, and because the volume within the sealed chamber must remain constant, the latex is blown out or sucked in. The construction also includes commercially-available fasteners, o-rings and components salvaged from various camera lenses, such as glass elements and an aperture mechanism. As can be seen by the example photo above, the degree of focus that can be achieved with these materials is quite low- however the design offers a new and interesting way to consider fabricated optics by drawing inspiration from biology.